JP2848686B2 - Heating and cooling machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a warming / cooling machine that uses a compressor during a cooling operation and uses a refrigerant conveying means and a refrigerant heater other than the compressor during a heating operation. is there.

2. Description of the Related Art Conventionally, this type of heating / cooling machine has a configuration as shown in FIG. 5, for example.

That is, the heater / cooler includes a compressor 51 having a compressor heater 52, a four-way valve 53, an outdoor heat exchanger 54, an outdoor heat exchanger blower 55, a first solenoid valve 56, and a capillary tube 57. And the indoor heat exchanger 58 and the indoor heat exchanger blower 59
, A second solenoid valve 60, a check valve 61, an accumulator 62
, A third solenoid valve 63, a refrigerant pump 64, a refrigerant heater 65
In the cooling operation, the outdoor heat exchanger 54 is used as a condenser, and the indoor heat exchanger 58 is used as an evaporator to constitute a cooling cycle by operating the compressor 51. Is the evaporator by heating the refrigerant heater 65 with the burner 66, the indoor heat exchanger 58 is a condenser, and the refrigerant pump
A heating cycle is configured with 64 as the refrigerant transport means, and the compressor
The compressor 51 is heated by the compressor heater 52 so as to prevent the refrigerant from accumulating in the refrigerant 51 and to shorten the pump-down operation, thereby maintaining a constant temperature.

With the above configuration, at the start of the heating operation, the first solenoid valve 56 is closed, the four-way valve 53 is switched so that the refrigerant gas discharged from the compressor 51 flows to the indoor heat exchanger 58, and the blower 59 for the indoor heat exchanger is further switched on. After the pump-down operation is performed by the compressor 51 in a state in which the compressor 51 is stopped, the operation of the refrigerant pump 64, the refrigerant heater 65, and the indoor heat exchanger blower 59 is started, and the compressor 51 is stopped.

Problems to be Solved by the Invention However, in the above configuration, at the time of starting the heating operation,
It is assumed that the compressor 51 is sufficiently heated by the compressor heater 52.For example, immediately after the unit is installed, or when the power is turned off for a long time, the compressor 51 becomes cold, and the outdoor heat exchange In a state where the refrigerant leaks into the heater 44 frequently, the refrigerant cannot be sufficiently recovered to the heating circuit side within the set pump down time, and the temperature of the refrigerant heater abnormally increases during the heating operation. However, there has been a problem that a normal heating operation cannot be performed due to a phenomenon such as heating.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a heating / cooling machine capable of stably performing a heating operation by sufficiently recovering a refrigerant to a heating circuit side at a start of a heating operation.

Means for Solving the Problems In order to solve the above problems, the heating and cooling device of the present invention, during cooling operation, comprises a compressor, an indoor heat exchanger, an outdoor heat exchanger and a throttling device, a refrigerant circuit, During the heating operation, a refrigerant conveying means other than the compressor, a heating and cooling machine that constitutes a refrigerant circuit by a variable calorific value heater and an indoor heat exchanger, and a temperature detecting means for detecting a temperature of the compressor, Refrigerant recovery means for recovering refrigerant in the outdoor heat exchanger to the indoor heat exchanger by driving the compressor, oil recovery means for recovering refrigerating machine oil in the refrigerant heater, these refrigerant recovery means, and oil recovery means When the temperature detected by the temperature detecting means of the compressor is higher than a predetermined temperature at the start of a heating operation, the refrigerant heater is driven at a high calorific value after the refrigerant recovery operation for a short time. The temperature is higher than the specified temperature After the refrigerant recovery operation for a long time when the temperature is lower, the detected temperature of the temperature detecting means of the compressor is compared again with a predetermined temperature, and when the temperature is higher than the predetermined temperature, the refrigerant heater is driven with a high calorific value,
When the detected temperature is lower than a predetermined value, a controller is provided for driving the refrigerant heater with a low heat amount for a predetermined time and then performing an oil recovery operation for a predetermined time by the oil recovery means.

Operation With the above configuration, the refrigerant recovery operation time at the start of the heating operation is short when the temperature of the compressor is high, and long when the temperature of the compressor is low, so that the refrigerant recovery required for the heating operation can be reliably performed, and the temperature of the compressor can be reduced. When the temperature is low, a stable heating operation can be performed by quickly and reliably recovering a large amount of refrigerating machine oil taken out.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a system block diagram of a heating / cooling machine according to one embodiment of the present invention. As shown in FIG. 1, a heating / cooling machine according to the present invention includes a compressor 1 having the same functions as the conventional one, a compressor heating heater 2 provided below the compressor 1, and a discharge of the compressor 1. A first check valve 3, a four-way valve 4, an outdoor heat exchanger 5, an outdoor heat exchanger blower 6 provided in the pipe,
An indoor heat exchanger 7, a blower 8 for the indoor heat exchanger, an accumulator 9, a refrigerant heater 10, and a combustion burner 11 for heating the refrigerant heater 10 are provided. The combustion amount is variable. Further, in addition to the above configuration, this heating / cooling machine includes a gas-liquid separator 12,
A first solenoid valve 14 disposed in a pipe 15 connecting the upper part of the liquid receiver 13 and the upper part of the gas-liquid separator 12 to the upper part of the liquid receiver 13, the lower part of the liquid receiver 13 and the lower part of the gas-liquid separator 12 And a third check valve 18 disposed in a pipe 19 connecting the indoor heat exchanger 7 and the upper part of the receiver 13.
And the fourth check valve 20 disposed in the pipe 22 connecting the pipe 21 between the first check valve 3 and the four-way valve 4 to the upper part of the gas-liquid separator 12, and the outdoor heat exchanger 5. A first capillary tube 23 and a second solenoid valve 24 arranged in series in a pipe 24 connecting the lower part of the refrigerant heater 10, and a pipe 28 between the lower part of the gas-liquid separator 12 and the lower part of the refrigerant heater 10; A third solenoid valve 26 and a second capillary tube 27 arranged in series in a pipe 29 connecting the pipe 19, a pipe 30 connecting the upper part of the refrigerant heater 10 and the upper part of the gas-liquid separator 12, 1 solenoid valve
There are provided a pipe 31 connecting the 14 and the second solenoid valve 24, a temperature detecting means 34 for measuring the temperature of the compressor 1, and a control device 35 to which the temperature detecting means 34 is connected.

In the above refrigerant circuit configuration, during the cooling operation, the four-way valve 4
Is switched so that the discharge gas of the compressor 1 flows to the outdoor heat exchanger 5 and the second solenoid valve 24 and the third solenoid valve 26 are opened, so that the first capillary tube 23 and the second capillary tube are opened.
A refrigerant circuit is provided in which 27 is a throttle device and the indoor heat exchanger 7 functions as an evaporator. During the heating operation, the four-way valve 4 is switched in the direction opposite to that during the cooling operation (the direction shown in FIG. 1).
By heating the refrigerant 10, the refrigerant in the refrigerant heater 10 is heated, and the refrigerant in the gaseous state, which has become high temperature in the gas-liquid separator 12, passes through the pipe 22, the check valve 20, and the four-way valve 4 for indoor heat exchange. Extruded into the heat sink 7 and radiated by the indoor heat exchanger 7 to heat the room, and the liquefied refrigerant liquid passes through the pipe 19 and the check valve 18 to the receiver 13.
Move inside. The refrigerant liquid accumulated in the receiver 13 opens the first solenoid valve 14 and guides the pressure of the gas-liquid separator 12, thereby causing a second reverse flow due to a drop between the receiver 13 and the gas-liquid separator 12. The gas is returned to the gas-liquid separator 12 via the stop valve 16. As described above, the opening / closing operation of the liquid receiver 13 and the first solenoid valve 14 and the check operation of the third check valve 18 allow the refrigerant as the heat transfer medium to be performed without operating the compressor 1. . That is, the liquid receiver 13, the first solenoid valve 14, and the third check valve 18 serve as the refrigerant conveying means 32.

By the way, before performing the heating operation, a recovery operation for recovering the refrigerant in the outdoor heat exchanger 5, the accumulator 9, and the compressor 1 not operating as the heating circuit to the heating circuit side is performed. That is, with the four-way valve 4 in the same direction as during the heating operation and the outdoor heat exchanger 5 connected to the accumulator 9, the compressor 1 is operated to remove the refrigerant of the outdoor heat exchanger 5, the accumulator 9 and the compressor 1. Collected in the indoor heat exchanger 7. At this time, the indoor heat exchanger blower 8 is operated to sufficiently liquefy the refrigerant in the indoor heat exchanger 7, thereby facilitating the return of the liquid refrigerant from the pipe 19 to the liquid receiver 13. Thus, the refrigerant recovery means 33 is constituted by the compressor 1, the first check valve 3 and the four-way valve 4.

When the refrigerating machine oil taken out to the heating circuit side during the heating operation is condensed into the refrigerant heater 10, the flow of the refrigerant in the refrigerant heater 10 deteriorates, and the heat exchange deteriorates, thereby causing abnormal heating. Due to the danger, it is necessary to recover oil early. When the second solenoid valve 24 is opened, the refrigerating machine oil condensed at the lower portion in the heater 10 flows out to the outdoor heat exchanger 5. The spilled oil can be collected in the compressor 1 by operating the compressor 1. That is, the second solenoid valve 24 is an oil recovery unit.

The control device 35 controls the drive of the refrigerant recovery means 33 and the oil recovery means (second electromagnetic valve) 24 and controls the amount of combustion of the combustion burner 11. The control device 35 includes a recovery control unit 36 that drives the refrigerant recovery unit 33, a strong combustion control unit 37 of the combustion burner 11,
A weak combustion control section 38 of the combustion burner 11, an oil recovery control section 39 for driving the oil recovery means 24, and first to fourth timers 40, 41, 44, 4
5 (the second timer 41 has a longer set time than the first timer 40), a switching unit 42 for switching between the first timer 40 and the second timer 41, and a detection temperature Tc of the temperature detection means 34. Is compared with a predetermined temperature Ts.

The operation of the control device 35 will be described with reference to FIG.

First, when the heating operation is started, in the comparison unit 43,
The temperature Tc of the compressor 1 detected by the temperature detecting means 34 is compared with a predetermined temperature Ts (step S ₁ ). When the detected temperature Tc is higher than the predetermined temperature Ts, the setting time is set via the switching unit 42. Start the first timer 40, which is short (step
S _2), is to start a long second timer 41 set time when the detected temperature Tc is lower than the predetermined temperature Ts (step
S _3). In any case, the recovery control unit 36 is operated until the timers 40 and 41 elapse the set time, and the refrigerant recovery means 33
(Steps S ₄ and S ₅ ), and stops the refrigerant recovery means 33 when the timers 40 and 41 elapse the set time (Steps S ₄ and S ₅ ).
S _6, S _7). When the first timer 40 is operated and the set time has elapsed, the strong combustion control unit 37 is operated to activate the combustion burner.
11 is driven by the intense combustion (step S _8). Second timer
41 is activated and when the set time has elapsed, again
The comparing unit 43 compares the detected temperature Tc of the temperature detecting means 34 of the compressor 1 with the predetermined temperature Ts (step S ₉ ). When the detected temperature Tc is higher than the predetermined temperature Ts, the strong combustion control unit 37 sets the combustion burner 11 to strong. is burned (step S _10), if the detected temperature Tc is lower than the predetermined temperature Ts is starts the third timer 44 (step S _11). Then, the weak combustion control unit 38 is operated until the third timer 44 elapses the set time, and the combustion burner is operated.
11 driven by the weak combustion (step S _12), the third timer 4
Stop the weak combustion at the elapse of the set time in Step 4 (Step S
₁₃₎ together to start the fourth timer 45 (step S _14). Further, the oil recovery control unit 39 is operated until the fourth timer 45 elapses the set time to drive the second solenoid valve 24 as the oil recovery means (step S ₁₅ ).
Setting time at 5 to stop the oil-recovery operation (step S ₁₆₎ to start the first timer 40 (step S _2).

As shown in FIG. 2, the recovery time of the refrigerant depends on the temperature of the compressor 1 and is short when the temperature is high and long when the temperature is low. The temperature is set slightly lower than the temperature, and the required refrigerant recovery time t ₁ required at the set temperature Ts
Was the setting time of the first timer 40, the time t ₂ corresponding to the temperature T _L close to the minimum outside air temperature during the heating operation period by the set time of the second timer 41, the temperature of the compressor 1 Accordingly, the refrigerant is sufficiently recovered, and the heating operation can be performed. Thus, when the temperature of the compressor 1 is sufficiently high, a short refrigerant recovery operation is sufficient, and power consumption during refrigerant recovery can be reduced. When the temperature of the compressor 1 is low, a large amount of refrigerating machine oil is taken out as shown in FIG. 3, but since the combustion burner 11 is operated in a weak combustion mode for a certain time after the refrigerant recovery operation, the temperature rise in the refrigerant heater 10 is increased. It is possible to perform continuous operation by being held down, and to condense the refrigerating machine oil taken out to the heating circuit side during the heating operation to the refrigerant heater 10 and then drive the second solenoid valve 24 as oil recovery means. Reliable oil recovery can be performed, and the next heating operation can be stabilized.

Effects of the Invention As described above, according to the heating / cooling device of the present invention, the following effects can be obtained.

(1) The refrigerant recovery operation time at the start of the heating operation is determined by detecting the temperature of the compressor and determining the first time when the temperature is higher than a predetermined temperature.
By shortening the time by the timer (1) and increasing the time by the second timer when the temperature is low, the refrigerant required for the heating circuit can be reliably recovered, and a stable heating operation can be obtained.

(2) Even when the compressor temperature at the start of the heating operation is low, the second
When the compressor temperature is higher than the predetermined value after the refrigerant recovery operation by the long timer, the initial temperature of the compressor is relatively high, so that the refrigerating machine oil is not taken out, and the refrigerant recovery is sufficiently performed. Operation can be eliminated, and a stable heating operation can be shifted relatively quickly.

(3) When the temperature of the compressor is high and the recovery operation time may be short at the start of the heating operation, the heating start-up is quick and the power consumption can be reduced to shorten the refrigerant recovery operation.

(4) A large amount of refrigerating machine oil is taken out during the refrigerant recovery operation when the compressor temperature is low. However, the heating operation is performed with weak combustion for a certain period of time, and the oil recovery is performed early and surely. Stabilization becomes possible.

[Brief description of the drawings]

FIG. 1 is a system block diagram of a heating / cooling machine according to an embodiment of the present invention, FIG. 2 is a characteristic diagram of a compressor temperature and a refrigerant recovery required time of the heating / cooling machine, and FIG. FIG. 4 is a characteristic diagram of the machine temperature and the amount of refrigerating machine oil taken out, FIG. 4 is a flowchart showing the flow of processing of the heating and cooling machine, and FIG. 5 is a system block diagram of a conventional heating and cooling machine. 1 ... Compressor, 5 ... Outdoor heat exchanger, 7 ... Indoor heat exchanger, 10 ... Refrigerant heater, 11 ... Variable combustion burner,
23 ... first capillary tube, 27 ... second capillary tube, 32 ... refrigerant conveying means, 33 ... refrigerant collecting means,
34 ... temperature detection means, 35 ... control device, 36 ... refrigerant recovery control unit, 37 ... strong combustion control unit, 38 ... weak combustion control unit, 39
... Oil recovery control section, 40 first timer, 41 second timer, 42 switching section, 43 comparison section, 44 third timer, 45 fourth timer.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-195867 (JP, A) JP-A-3-95361 (JP, A) (58) Fields investigated (Int.Cl. ⁶ , DB name) F25B 1/00 399 F25B 13/00 341 F24F 11/02 102

Claims (1)

(57) [Claims] In a cooling operation, a refrigerant circuit is constituted by a compressor, an indoor heat exchanger, an outdoor heat exchanger and a throttling device. A heating and cooling machine comprising a refrigerant circuit with a heat exchanger and an indoor heat exchanger, wherein a temperature detecting means for detecting the temperature of the compressor, and driving the compressor to transfer the refrigerant of the outdoor heat exchanger to the indoor heat exchanger. Refrigerant recovery means for recovering, oil recovery means for recovering refrigerating machine oil in the refrigerant heater, these refrigerant recovery means,
The oil recovery means and the refrigerant heater are connected, and when the detected temperature of the temperature detection means of the compressor is higher than a predetermined temperature at the start of the heating operation, after the refrigerant recovery operation for a short time, the refrigerant heater is driven at a high calorific value. When the detected temperature is lower than the predetermined temperature, after the refrigerant recovery operation for a long time, the detected temperature of the temperature detecting means of the compressor is compared with the predetermined temperature again, and when the detected temperature is higher than the predetermined temperature, the refrigerant heater is driven with a high calorific value. A control device for driving the refrigerant heater with a low heat amount for a predetermined time when the detected temperature is lower than a predetermined value, and then performing an oil recovery operation for a predetermined time by the oil recovery means.